Inulin hydrogels as carriers for colonic drug targeting: I. Synthesis and characterization of methacrylated inulin and hydrogel formation.
OBJECTIVE
Vinyl groups were introduced in inulin chains in order to form hydrogels of this sugar polymer by free radical polymerization.


METHODS
Inulin was reacted with glycidyl methacrylate in N,N-dimethylformamide in the presence of 4-dimethylaminopyridine as catalyst. 1H and 13C NMR spectroscopy were used for the characterization of the obtained reaction product. Solid state 13C NMR spectroscopy revealed the conversion of the incorporated vinyl groups into covalent cross-links upon free radical polymerization of aqueous solutions of the derivatized inulin.


RESULTS
During reaction of inulin with glycidyl methacrylate, transesterification occurred, leading to the direct attachment of the methacryloyl group to inulin. Consequently, the obtained reaction product is methacrylated inulin. The extent of chemical modification of inulin could be tuned by varying the molar ratio of glycidyl methacrylate to inulin in the reaction mixture. Aqueous solutions of methacrylated inulin were converted into cross-linked hydrogels by free radical polymerization using ammonium persulphate and N,N,N',N'-tetramethylethylenediamine as initiating system.


CONCLUSIONS
Inulin hydrogels can be formed by free radical polymerization of aqueous solutions of methacrylated inulin.
Vervoort
L
L
Laboratorium voor Farmacotechnologie en Biofarmacie, K.U. Leuven, Belgium. liesbeth.vervoort@farm.kuleuven.ac.be
Van den Mooter
G
G
Augustijns
P
P
Busson
R
R
Toppet
S
S
Kinget
R
R
D015761:4-Aminopyridine / Q000031:analogs & derivatives / Q000737:chemistry; D004126:Dimethylformamide / Q000737:chemistry; D004337:Drug Carriers; D004852:Epoxy Compounds / Q000737:chemistry*; D004951:Esterification; D005782:Gels; D007444:Inulin / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis*
D004337:Drug Carriers; D004852:Epoxy Compounds; D005782:Gels; D008689:Methacrylates; D011108:Polymers; D004126:Dimethylformamide; D007444:Inulin; D015761:4-Aminopyridine; C003885:4-dimethylaminopyridine; C007870:glycidyl methacrylate